import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        int i = 0;

        Scanner scanner = new Scanner(System.in);
        String tem1 = scanner.next();
        String tem2 = scanner.next();

        String reust = null;
        for (i = 0; i < tem2.length(); i++) {

            char tem3 = tem2.charAt(i);

            String charStr = String.valueOf(tem3);

            reust = tem1.replaceAll(charStr, "");
        }
        System.out.println(reust);
    }
}
